src/core/common/heap_string.cpp

/*
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/**
 * @file
 *   This file implements the `Heap::String` (a heap allocated string).
 */

#include "heap_string.hpp"

#include "common/code_utils.hpp"
#include "common/string.hpp"

namespace ot {
namespace Heap {

Error String::Set(const char *aCString)
{
    Error  error = kErrorNone;
    size_t curSize;
    size_t newSize;

    VerifyOrExit(aCString != nullptr, Free());

    curSize = (mStringBuffer != nullptr) ? strlen(mStringBuffer) + 1 : 0;
    newSize = strlen(aCString) + 1;

    if (curSize != newSize)
    {
        char *newBuffer = static_cast<char *>(Heap::CAlloc(sizeof(char), newSize));

        VerifyOrExit(newBuffer != nullptr, error = kErrorNoBufs);

        Heap::Free(mStringBuffer);
        mStringBuffer = newBuffer;
    }

    memcpy(mStringBuffer, aCString, newSize);

exit:
    return error;
}

Error String::Set(String &&aString)
{
    VerifyOrExit(mStringBuffer != aString.mStringBuffer);

    Heap::Free(mStringBuffer);
    mStringBuffer         = aString.mStringBuffer;
    aString.mStringBuffer = nullptr;

exit:
    return kErrorNone;
}

void String::Free(void)
{
    Heap::Free(mStringBuffer);
    mStringBuffer = nullptr;
}

bool String::operator==(const char *aCString) const
{
    bool isEqual;

    VerifyOrExit((aCString != nullptr) && (mStringBuffer != nullptr), isEqual = (mStringBuffer == aCString));
    isEqual = (strcmp(mStringBuffer, aCString) == 0);

exit:
    return isEqual;
}

} // namespace Heap
} // namespace ot